Notwithstanding any other provisions of this section, if a member retires before attaining the age of 65 years, his or her elective COLA shall be actuarially reduced to reflect that earlier retirement age unless, within 120 days after his or her retirement, he or she contributes by lump-sum the amount necessary to complete the purchase of his or her elective COLA as determined by the board. If, upon a member's retirement, the board of retirement determines that a member has paid more contributions than necessary to purchase his or her elective COLA in accordance with subdivision (b), the member shall receive a refund of those excess contributions and all interest credited thereto. Upon retirement or termination of employment, but before he or she begins receiving his or her elective COLA, a member may revoke his or her election to purchase an elective COLA and receive a refund of any contributions made toward the purchase of the elective COLA and all interest credited thereto.
Ca. Gov. Code § 31495.5